yet another chev starter prob
 

85 silverado, 350, tried shimming, and it started grinding, took the smallest shim out, now it sounds and starts like its shimmed too close, 2nd starter, 2nd set of shims, once i replaced the starter, it started just fine the first dozen times, but after the motor got to operating temp, is when the trouble started, any guesses?

Have you checked the clearance of the flywheel and starter gear when it is meshed. I see you are messing with the shims but you must also take measurements when changing them around..

not sure how, this is the first time ive had this problem, and what specs should i be looking for?

A large paper clip will give you a good mesaurment, .020

here is a link to check out
http://answers.yahoo.com/question/in...5230519AAf8atQ

Here is a link with pictures to show what you are after I'd stay with the .020 measurement cause it is kind of middle of the road..

You want to make the measurement for the clearance between the starter gear and flywheel in figure 1,

not that backlash pictured above figure 1

http://www.hitachi-hap-la.com/Downlo..._PE_106-en.pdf